1. VTOL AIRCRAFT AND PROPULSION SYSTEMS
The conventional helicopter is a VTOL vehicle which has a limited forward speed and range.
The V-22 Osprey is a helicopter with a rotor that tilts forward. The rotor has a high radar, low light and noise signature.
The Harrier “Jump” jet (AV 8A) uses the Pegasus turbofan engine. Thrust is vectored by nozzles that rotate in unison. Speed is limited to slightly above the speed of sound and the aircraft has a high radar and infrared signature.
The Lockheed Martin Joint Strike Fighter (JSF) concept is described by Bevilaqua and Shumpert in U.S. Pat. No. 5,209,428 dated May 11, 1993. The Lockheed Martin JSF concept has a 3-bearing swivel duct, a variable nozzle, and lift fan. Bevilaqua and Shumpert do not describe a 3-bearing swivel duct or variable nozzle.
Bollinger in U.S. Pat. No. 5,275,306 dated Jan. 4, 1994 describes a aircraft with a horizontal lift fan driven by exhaust air. The description is similar to Bevilaqua and Shumpert in other respects.
Zimmerman in U.S. Pat. No. 3,972,490 dated Aug. 3, 1994 describes a tri-fan powered VSTOL aircraft that uses turbo-tip fans and has a horizontal lift fan in the nose of the aircraft.
The Boeing JSF concept is described by Burnham et al in U.S. Pat. No. 5,897,078 dated Apr. 27, 1999. The aircraft described has rotational lift nozzles near the center of the aircraft, the exhaust duct nozzle can be closed and the aircraft has yaw, pitch and roll nozzles that stabilize the aircraft in a hover. The aircraft uses a F-119 derivative engine, positioned near the air intake.
Snell in U.S. Pat. No. 4,038,818 dated Aug. 2, 1977 describes a gas turbine power plant that has a series flow when air from the fan enters the engine core and a parallel flow in which the fan-driven air flow does not enter the engines core.
Musgrove in U.S. Pat. No. 4,474,345 dated Aug. 2, 1984 describes a series parallel gas turbine power plant used in a VTOL aircraft.
Nightingale in U.S. Pat. No. 4,587,803 dated May 13, 1986 describes a series parallel turbo machine where a sliding sleeve changes flows into a variable cycle engine with a series and parallel flows.
Roberts in U.S. Pat. No. 5,107,675 dated Apr. 28, 1992 describes a series parallel gas turbine power plant using rotational nozzles that connect a forward fan to a aft turbofan engine.
Snell in U.S. Pat. No. 5,996,935 dated Dec. 7, 1999 describes power plants for VSTOL aircraft, in which the variable series parallel power plants described by Snell in 1977 is used in a VTOL aircraft. Snell describes a rotational nozzle system similar to Roberts, in which a forward fan drives air into rotational nozzles that can be connected to a aft turbofan. The rotational nozzles can also be closed by rotational valves and fan flow directed into a main turbofan engine. The VTOL fan is located forward in the aircraft to create a balance in a hover.
2. THRUST VECTORING COWLS, HOODS, BONNETS, AND CONDUITS
Sokhey et al in U.S. Pat. No. 5,769,317 dated Jun. 23, 1998 describes a segmented conduit with rotating vanes and flaps that control thrust vectoring.
Nash in U.S. Pat. No. 4,000,610 dated Jan. 4, 1977 describes a cowl, or deflector, that has a variable throat for a vertical takeoff and landing aircraft.
Adamson in U.S. Pat. No. 4,222,234 dated Sep. 16, 1980 describes a vectoring “lobster tail” nozzle that is a segmented hood.
Scrace in U.S. Pat. No. 4,660,767 dated Apr. 28, 1987 describes a cowl system similar to Nash.
Horinouchi in U.S. Pat. No. 4,587,804 dated May 13, 1986 describes the thrust deflector or hood that has a variable throat and is used to create vertical thrust.
3. THRUST VECTORING ROTATIONAL VANES
Thayer and Stevens in U.S. Pat. No. 4,805,401 dated Feb. 21, 1989 describes a thrust vectoring exhaust nozzle using rotational vanes. Thayer describes a system that maintains a minimum flow, or fluid discharge area for engine function, and vectors thrust through a plurality of rotational vanes.
Madden in U.S. Pat. No. 4,690,329 dated Sep. 1, 1987 describes a door and rotational vanes that reverse thrust of a turbofan engine. The invention has a method of closing the exhaust duct to force engine exhaust flows to exit through thrust reversing ports.
Garland in U.S. Pat. No. 4,948,072 dated Aug. 14, 1990 describes a cascade of rotational vanes to which can vector thrust and regulates opening of the port.
4. THRUST VECTORING FLAPS
Herrick, Thayer and Steward in U.S. Pat. No. 4,836,451 dated Jun. 6, 1989 describes a nozzle with a variable throat area that uses flaps and a gimbaled system. The nozzle throat can be closed and exhaust gases passed through ports on the sides of the exhaust duct. Exhaust gas flows through ports is used to reverse thrust and for thrust vectoring.
Meister in U.S. registration No. H1024 dated Mar. 3, 1992 describes a thrust vectoring and reversing structure with a rotating flap or vane in the exhaust duct flow.
Cockerham in U.S. Pat. No. 5,161,752 dated Nov. 10, 1992 describes a system having four ports that uses flaps to develop yaw and pitch control while maintaining engine back pressure by closing the exhaust nozzle.
Cockerham in U.S. Pat. No. 5,255,850 dated Oct. 28, 1993 describes a nozzle reverser assembly using flaps and having a exhaust nozzle that can be closed.
Holowach in U.S. Pat. No. 5,690,280 dated Nov. 25, 1997 describes a flap system on the exhaust duct that is capable of numerous exhaust gas exit configurations. The positioning of flaps within the exhaust flow would create a high infrared signature.
Lowman in U.S. Pat. No. 4,074,859 dated Feb. 21, 1978 describes a flap system to vector and reverse thrust. It's systems is somewhat similar to Holowach.
5. THRUST VECTORING VARIABLE NOZZLES
Nash in U.S. Pat. No. 4,175,385 dated Nov. 27, 1979 describes a variable throat thrust reversing exhaust nozzle with a cowl for vertical lift.
Beaver in U.S. Pat. No. 3,986,687 dated Oct. 19, 1976 describes a aircraft propulsion system having a flight reversible nozzle with thrust vectoring, super circulation and variable throat control.
Madden in U.S. Pat. No. 4,587,806 dated May 13, 1986 describes a variable throat asymmetric two-dimensional converging diverging nozzle for thrust vectoring and directing thrust vertically.
Nash in U.S. Pat. No. 4,361,281 dated Nov. 30, 1982 describes the exhaust nozzle that can be closed and has variable convertent divergent form but is not for thrust vectoring.
Wooten in U.S. Pat. No. 4,280,660 dated Jul. 28, 1981 describes a variable throat nozzle that can vector thrust up to 60 degrees.
Szuminski in U.S. Pat. No. 4,519,543 dated May 28, 1985 describes a rotatable duct that can turn a nozzle through 90 degrees to vector thrust down.
Taylor and Nash in U.S. Pat. No. 5,351,888 dated Oct. 4, 1994 describes a “multi-axis vectorable exhaust nozzle” for thrust vectoring.
6. ENGINE CONTROL
Neitzel in U.S. Pat. No. 4,791,781 dated Dec. 20, 1988 describes variable inlet and outlet guide vanes which lessen the outer load on the fan allowing power to be diverted to another fan or rotor.
Many of the patents mentioned have some engine control system to maintain minimum throat area and engine back pressures.
7. VARIABLE PITCH FANS
Dumbar in U.S. Pat. No. 5,794,432 dated Aug. 18, 1998 describes variable inlet, outlet and stator blades on a fan.
Griswold in U.S. Pat. No. 3,994,128 Nov. 30, 1976 describes a variable pitch turbofan system.
Avena in U.S. Pat. No. 4,047,842 dated Sep. 13, 1977 describes a variable pitch mechanism for fan blades.
McCarty in U.S. Pat. No. 5,282,719 dated Feb. 1, 1994 describes the pitch actuator system for a gas turbine engine.